Electric heater



E. N. UGHTEooT. l

ELECTRIC HEATER. APPLICTION FILED APR. 9. 1920.

1,403,330, A Patented Jan. 10, 1922'.

' ATTORNEY EDWIN N'. LIGHTFOOT, 0F NEW YORK, N. Y., ASSIGNOR TO T HE CUTLER-I-IAMMER MFG. CO., OF MILWAUKEE, WISCONSIN, CORPORATION OF WISCONSIN.

ELECTRIC HEATER.

Application filed April A9,

To @Z510/1,0m it may concern Be it known that l, EDWIN N. Liorrrroor, a citizen oi the United States, residing at New York, in the county of Bronx and State of N ew York, have invented new and useful Improvements in an Electric Heater, of which the following is a specification.

This invention relates to an electric heater.

This electric heater is particularly useful in press blocks of printing presses, although not limited to such use.

An object of this invention is to provide a simple, durable and efficient press block heater.

Another object is to provide an improved press block heater, the heating effect ot which may be easily and quickly varied.

Another object is to provide an improved heater wherein the` possibility oi damaging the heater when subjected to pressures ot' considerable magnitude is reduced.

Another object is to provide an improved press block heater having a plurality of heating units which may be inter-connected in various combinations to obtain the desired heating effect.

Other objects and advantages will appear from the following description.

An embodiment of the invention is `illustrated in the accompanying drawings, wherein Figure 1 is a top plan of the press block heater with the top or cover plate removed;

Fig. 2 is a vertical transverse section on line 2 2 of Fig. 1;

Fig. 3 is a vertical transverse section on line 3 3 of Fig. 1;

Fig. 4 is a sectional View through one ot the heater units on line 4 4 of Fig. 1; and

Fig. 5 is a perspective of the press block heater.

The press block heater has a bottom plate 10, provided with a plurality of channels or pockets 11, for the reception ot' the heater units 12, 13 and 14. These channels or pockets 11 communicate with a transverse channel or pocket 15, which contains conducting strips connecting the terminals of the heater units with the terminals of the heater. A top or cover plate 16 may be suitably secured to the bottom plate 10 by screws 17, which are counter sunk, so that they do not project above the surface of the cover plate 16.

Each heater unit is made up of two flat heaters 12EL and 12b, ete. Each iiat heater Specification of Letters Patent.

Patented J an. 10, 1922. i920. Serial No. 372,615.

comprises'a resistor 18 in the form ot' a ribbon wound on an insulating core 19. The resistors of the two flat heaters of the units are connected in series by a resistor strip 20, or the resistors for each unit may be continuous. The two flat heaters-of the unit are enclosed in an armor of two plates 25 and 26, the latter having flanges folded over the former. Insulating strips 27 and 28 separate the resistor ribbons fromr thel armor plates 25 and 26.

The heater is provided with three plug terminals 30, 31 and 32, carried by an insulating strip 33, and extending through openings in a supporting bracket 34. lnsulating bushings are interposed between the terminal plugs and the edges of the openings in the bracket 34. The supporting bracket 34 is suitably secured to the front of the bottom plate 10 by screws 35.

One terminal of each heater unit is connected to a common conducting strip 36, which is in turn connected to the plug terminal 30 by means of a conducting strip 3T. rlhe other terminal of the heater units 12 and 14 are connected to a common conducting strip 38, which is in turn connected to the plug terminal 31 by means of a. strip 39. The other terminal of the heater unit 13 is connected to the plug terminal by means or' a conducting strip 40. These conducting stripsare suitably insulated from each other and Afrom the bottom and top plates by means of insulating strips 41, 42, 43 and 44. The conducting strips 37, 39 and 40 connected to the plug terminals extend through a slot in the iront of the bottom plate 10, and are nsulated therefrom by an insulating strip 45, and. from the top plate by an insulating strip 46.

The heater may be connected with the source of current supply by means of a three contact socket 50, to which is connected a three conductor cord or cable 51. This three conductor cord orcable may be connected with three terminals of a tive terminal control switch (not shown), to the other two terminals of which is connected the source of current supply.

The heater units 12 and 14 are connected in parallel between plug terminals 30 and 31, while heater unit 13 is connected between plug terminals 30 and 32. By arranging the heating units in this manner three degrees ot heat may be obtained from this cards, etc.

all three heating units are in service. units 12 and 1st being connected in parallel relation and in series with unit 18. The mediumy degree ofV heat is obtained by'employing units 12 and 14 connected in parallel, While to obtain the low degree of heat, heatingV unit 13 only is employed. f

V A control switch of any Well known` type connected in circuit with the cablel and the source of current supply may be ernployed to switch the heating units into different arrangements Wherebyfany oneV of the three degrees of heat are obtained from this heater. Y Y Y The construction ofV this heater is such that it is very compact and thin, yet the resister or heating elementsthereof `are thoroughly insulated. Thus there isvproduced a highly etlicient electric heater which is so thin that it may be employed in very shallow spaces.V F or example, t-his heater may be very efficiently' used in piess blocks associated'With the embossing plates employed in printing aresses Vfor embossing paper, uch press blocks are usually Y limited in thicknessto about six hundred and twenty-five thousandths (.625) of Van.

inch, and theV heaters are mounted insidethe press block.

The described heater is of ,very rugged construction, so that the-heater will stand up under severe operating conditions, such:

1.7An electric Vheater comprising aliiat plate having a plurality of channels commuplate having a plurality of channels communit-ating with a channel common thereto, a

resistance element in each ofthe plurality Y of channels, a bracket secured to the plate and lying in the plane thereof, terminals for the heaterA supported by thebracket, Vand conductors positioned in the common channel and connecting the resistance elements to the terminals. l I Y 3. An electric Yheater' comprising` aiiat plate having a channel therein, a resistance element in said. channel, a bracket secured to one edge of the plateand lying in theV plane of the plate, and. terminals for the' heater connected tothe resistance element and supported by the bracket in the plane of Vthe-plate. y

4. An electric heater comprising a flat plate having a plurality of channels therein, a plurality of resistors in each channel, the resistors of the several channels being convnected in various combinations, and terminals connected to the resistors and supported by the plate in the plane thereof. l

5. An electric heater comprising a fiatV plate having a plurality of channels therein, ar resistance element in each channel, a bracket secured to the plate and lying in the Vplane thereof, terminals connected to the resistance elements and supported in the plane of the plate by the bracket, and acover for the 1 channels. Y In witness whereof l have hereunto subscribed Vmy name.

sof

c EDWIN N. Lienrroo'r. Y Y 

